Three-dimensional shaping apparatus

ABSTRACT

To provide a three-dimensional shaping apparatus excellent in accuracy and productivity. In a three-dimensional shaping apparatus  1 , a shaped article placing part  4  includes a table  41  on the upper surface of which a shaped article is placed, a drive part  45  that drives the table  41 , measurement parts  46  and  47  that measure the position of the table  41  or the position of a slider  42 , and a controller  50  that controls the drive part  45  on the basis of measurement values from the respective measurement parts  46  and  47.

This is a National Stage of International Application No.PCT/JP2015/066352 filed Jun. 5, 2015, claiming priority based onJapanese Patent Application No. 2014-125077 filed Jun. 18, 2014, thecontents of all of which are incorporated herein by reference in theirentirety.

TECHNICAL FIELD

The present invention relates to a three-dimensional shaping apparatusthat produces a three-dimensional shaped article by repeatedly formingpowder into a layer.

BACKGROUND ART

There is disclosed a three-dimensional shaping apparatus that repeatedlyperforms a sintering operation including irradiation of a metal powderlayer with a focused energy beam to produce a three-dimensional shapedarticle composed of a plurality of sintered bodies (see Patent Documents1 and 2).

CITATION LIST Patent Document

Patent Document 1: JP 2011-127195A

Patent Document 2: JP-T 2006-511710

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

An object of the present invention is to provide a three-dimensionalshaping apparatus excellent in accuracy and productivity.

Means for Solving the Problems

A three-dimensional shaping apparatus according to an embodiment of thepresent invention includes: a support frame; a material supply partsupported by the support frame; and a shaped article placing part whichis supported by the support frame and on which a material supplied fromthe material supply part is placed, wherein the shaped article placingpart includes: a table on the upper surface of which the shaped articleis placed; a drive part that drives the table; a measurement part thatmeasures the position of the table; and a controller that controls thedrive part on the basis of a measurement value from the measurementpart.

The three-dimensional shaping apparatus according to the embodiment ofthe present invention further includes: an input part that previouslyinputs thereto the moving amount of the table; and a storage part thatstores the moving amount input to the input part, wherein the controllermoves the table by the moving amount stored in the storage part.

In the three-dimensional shaping apparatus according to the embodimentof the present invention, state signals of the drive part is fed back tothe controller.

The drive part includes first and second drive parts which can beindependently driven, the measurement part includes first and secondmeasurement parts that measure the position of the table, and thecontroller independently controls the first and second drive parts onthe basis of measurement values from the first and second measurementparts.

In the three-dimensional shaping apparatus according to the embodimentof the present invention, the shaped article placing part furtherincludes a transmission part having first and second transmission partsthat transmit drive forces supplied from the respective first and seconddrive parts to the table.

In the three-dimensional shaping apparatus according to the embodimentof the present invention, the first and second measurement parts aredisposed so as to correspond to the positions of the first and secondtransmission parts that support the table.

In the three-dimensional shaping apparatus according to the embodimentof the present invention, the drive part includes the first to fourthdrive parts arranged in a rectangular shape, the transmission partincludes first to fourth transmission parts that transmit drive forcessupplied from the respective first to fourth drive parts to the table,and the controller can independently control the first to fourth driveparts.

The three-dimensional shaping apparatus according to the embodiment ofthe present invention includes: a rod moved together with the table; anda limit switch put in contact with the rod when the rod reaches apredetermined position.

Advantages of the Invention

According to the present invention, there can be provided athree-dimensional shaping apparatus excellent in accuracy andproductivity.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view illustrating a three-dimensional shaping apparatusaccording to an embodiment of the present invention;

FIG. 2 is an enlarged view illustrating a shaped article placing part ofthe three-dimensional shaping apparatus according to the presentembodiment;

FIG. 3 is a schematic view illustrating an arrangement in a drivetransmission part of the three-dimensional shaping apparatus accordingto the present embodiment;

FIG. 4 is a schematic perspective view illustrating the shaped articleplacing part of the three-dimensional shaping apparatus according to thepresent embodiment;

FIG. 5 is a view illustrating a control system of the three-dimensionalshaping apparatus 1 according to the present embodiment;

FIG. 6 is an enlarged view illustrating an operation of the shapedarticle placing part of the three-dimensional shaping apparatusaccording to the present embodiment;

FIG. 7 is an enlarged view illustrating an operation of the shapedarticle placing part of the three-dimensional shaping apparatusaccording to the present embodiment;

FIG. 8 is an enlarged view illustrating an operation of the shapedarticle placing part of the three-dimensional shaping apparatusaccording to the present embodiment;

FIG. 9 is an enlarged view illustrating an operation of the shapedarticle placing part of the three-dimensional shaping apparatusaccording to the present embodiment;

FIG. 10 is a view illustrating a state where a shaped article is formedby the three-dimensional shaping apparatus according to the presentembodiment;

FIG. 11 is a view illustrating a three-dimensional shaping apparatusaccording to another embodiment of the present invention;

FIG. 12 is a schematic view illustrating an arrangement in the drivetransmission part of the three-dimensional shaping apparatus accordingto the another embodiment;

FIG. 13 is a schematic view illustrating an arrangement in the drivetransmission part of a three-dimensional shaping apparatus according toa still another embodiment;

FIG. 14 is a schematic view illustrating an arrangement in the drivetransmission part of a three-dimensional shaping apparatus according toa still another embodiment;

FIG. 15 is a schematic view illustrating an arrangement in the drivetransmission part of a three-dimensional shaping apparatus according toa still another embodiment;

FIG. 16 is a schematic view illustrating a structure of the drivetransmission part of the three-dimensional shaping apparatus accordingto the present embodiment;

FIG. 17 is a schematic view illustrating a structure of the drivetransmission part of a three-dimensional shaping apparatus according toanother embodiment;

FIG. 18 is a schematic view illustrating a structure of the drivetransmission part of a three-dimensional shaping apparatus according tostill another embodiment;

FIG. 19 is a schematic view illustrating a structure of the drivetransmission part of a three-dimensional shaping apparatus according tostill another embodiment;

FIG. 20 is a schematic view illustrating a structure of the drivetransmission part of a three-dimensional shaping apparatus according tostill another embodiment; and

FIG. 21 is a schematic view illustrating a structure of the drivetransmission part of a three-dimensional shaping apparatus according tostill another embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 is a view illustrating a three-dimensional shaping apparatusaccording to an embodiment of the present invention.

A three-dimensional shaping apparatus 1 according to the presentembodiment includes an energy beam irradiation part 2 as a materialsupply part, a powder supply part 3 as a material supply part, and ashaped article placing part 4. The energy beam irradiation part 2,powder supply part 3, and shaped article placing part 4 are supported bya support frame 11. A reference frame 12 as a part of the support frame11 is formed at the intermediate portion of the support frame 11.

The energy beam irradiation part 2 includes a beam generation part 21that generates an energy beam EB and a beam scanning part 22 thatadjusts the focal position of the energy beam EB emitted from the beamgeneration part 21 and performs two-dimensional scanning. The energybeam irradiation part 2 is placed on the support frame 11. Although thebeam scanning part 22 is configured to perform the two-dimensionalscanning in the present embodiment, it may be configured to performthree-dimensional scanning in which the beam focal position can also beadjusted in a vertical direction.

The beam generation part 21 is preferably configured to generate a laserlight, an electron beam, or the like. When the energy beam EB is a lightbeam, the beam scanning part 22 moves an optical element such as a lensto converge the light beam on a metal powder M on a table to bedescribed later and two-dimensionally scans a table 41. In this case,for example, the energy beam irradiation part 2 may have a configurationlike the laser irradiation unit described in Patent Document 1. When theenergy beam is an electron beam, the beam scanning part 22 focuses theelectron beam under magnetic field control and two-dimensionally scansthe table 41. In this case, for example, the energy beam irradiationpart 2 may have a configuration like the device that emits and guides anelectron beam which is disclosed in Patent Document 2.

The powder supply part 3 includes a powder storage part 31 thattemporarily store the metal powder M, a leveling part 32 that levels themetal powder M on the table, and an outer frame part 33.

The powder storage part 31 is a container retained by the support frame11. The powder storage part 31 has an injection part 31 a for injectingthe metal powder M and a discharge part 31 b for discharging the metalpowder M at the upper and lower portions thereof, respectively. Thedischarge part 31 b is preferably configured to adjust the dischargeamount of the metal powder M.

The leveling part 32 is a part that moves a member like a scraper on thetable 41 to level the metal powder M discharged from the powder storagepart 31 to thereby form a plane having as much a uniform height aspossible. The height of the leveled metal powder M can preferably beadjusted.

The outer frame part 33 is supported by the support frame 11 andinstalled on the outer periphery of the table 41 to be described later.To the outer frame part 33, extra metal powder M is pushed out as aresult of the leveling operation of the leveling part 32. The extrametal powder M is preferably circulated to the powder storage part 31 byan unillustrated circulation part.

As described above, the unillustrated circulation part that returns, tothe powder storage part 31, the metal powder M that has not beensubjected to shaping after being discharged onto the table 41 from thedischarge part 31 may be formed in the powder supply part 3.

The material supply part is not limited to the energy beam irradiationpart 2 and the powder supply part 3 of the present embodiment but mayhave a configuration in which sheet-like or tape-like resins, pieces ofpaper, or metals are bonded, a configuration in which liquid is cured, aconfiguration in which an inkjet head is used to eject a solid or liquidfor bonding, a configuration in which a filament is deposited andwelded, or a configuration in which metal powder is welded.

FIG. 2 is an enlarged view illustrating the shaped article placing partof the three-dimensional shaping apparatus according to the presentembodiment. FIG. 3 is a schematic view illustrating an arrangement in adrive transmission part of the three-dimensional shaping apparatusaccording to the present embodiment. FIG. 4 is a schematic perspectiveview illustrating the shaped article placing part of thethree-dimensional shaping apparatus according to the present embodiment.

The shaped article placing part 4 includes a table 41, a slider 42, aball screw 43, a deceleration part 44, a table drive part 45, a magneticsensor 46, a magnetic scale 47, a rod 48, and a limit switch 49.

The table 41 is supported by the slider 42. The upper surface of thetable 41 is a flat surface, onto which the metal powder M illustrated inFIG. 1 is discharged and placed. A shaped article is preferably formedin a shaping area 41 having a smaller size than the external size of thetable 41.

The slider 42 supports the table 41 at its upper surface. The slider 42is supported at its lower portion by the ball screw 43. The ball screw43 is connected to a drive part 45 through the deceleration part 44. Thedrive part 45 includes a servo motor or other actuator. The drive of thedrive part 45 rotates the ball screw 43 to move the slider 42 in thevertical direction, thereby vertically moving the table 41. The ballscrew 43 is preferably configured to penetrate the reference frame 12.

More specifically, in the present embodiment, four ball screws 43, fourdeceleration parts 44, four drive parts 45, four magnetic sensors 46,and four magnetic scales 47 are provided. The ball screw 43 anddeceleration part 44 constitute a transmission part. Further, the drivepart 45 and transmission part constitute a drive transmission part. Inplace of using the deceleration part 44, a direct action mechanismconstituted of the drive part 45 and the ball screw 43 may be adopted.The direct action mechanism can suppress backlash, enabling more highlyaccurate control.

As illustrated in FIG. 3, a first ball screw 43 a, a second ball screw43 b, a third ball screw 43 c, and a fourth ball screw 43 d areconnected to the slider 42 at the outside of the shaping area 41 a so asto correspond to four corners of the slider 42.

As illustrated in FIG. 4, a first drive part 45 a, a second driver part45 b, a third drive part 45 c, and a fourth drive part 45 d areconnected respectively to the first ball screw 43 a, second ball screw43 b, third ball screw 43 c, and fourth ball screw 43 d through a firstdeceleration part 44 a, a second deceleration part 44 b, a thirddeceleration part 44 c, and a fourth deceleration part 44 d,respectively.

A first magnetic sensor 46 a, second magnetic sensor 46 b, a thirdmagnetic sensor 46 c, and a fourth magnetic sensor 46 d are fitted tothe lower surface of the slider 42 so as to correspond to the supportpositions of the first ball screw 43 a, second ball screw 43 b, thirdball screw 43 c, and fourth ball screw 43 d.

The magnetic sensor 46 is an example of a measurement part. Themeasurement part may alternatively be an optical position sensor thatdetects a distance using a light emitting part fitted to one of theslider 42 and the support frame 11 and a light receiving part fitted tothe other one of them or an ultrasonic wave sensor. Preferably, one ofthe light emitting part and the light receiving part is fitted to thereference frame 12 and the other fitted to the slider 42. As is the casewith the magnetic sensor 46, the optical position sensor or ultrasonicwave sensor is preferably fitted so as to correspond to the supportpositions of the first ball screw 43 a, second ball screw 43 b, thirdball screw 43 c, and fourth ball screw 43 d. Further alternatively, anunillustrated motor encoder that converts a motor rotation angle into astroke amount may be used together with the magnetic sensor 46 for finerposition detection.

The support frame 11 on the lateral sides of the slider 42 has a firstmagnetic scale 47 a, a second magnetic scale 47 b, a third magneticscale 47 c, and a fourth magnetic scale 47 d each formed with a magneticscale. The first to fourth magnetic scales 47 a to 47 d are disposedopposite to the first to fourth magnetic sensors 46 a to 46 d,respectively.

At least one of the first to fourth ball screws 43 a to 43 d is attachedwith the rod 48. The rod 48 is moved together with the table 41, slider42, and ball screw 43. The limit switch 49 is provided below the rod 48.Thus, when the table 41, slider 42, ball screw 43, and rod 48 areexcessively moved upward or downward, the limit switch 49 is activatedto inform an operator of danger.

The following describes a control system of the three-dimensionalshaping apparatus 1 according to the present embodiment.

FIG. 5 is a view illustrating a control system of the three-dimensionalshaping apparatus 1 according to the present embodiment.

As illustrated in FIG. 5, in the three-dimensional shaping apparatus 1according to the present embodiment, a controller 50 independentlycontrols the first to fourth drive parts 45 a to 45 d on the basis ofsignals input respectively from an input part 51, the first magneticsensor 46 a, the second magnetic sensor 46 b, the third magnetic sensor46 c, the fourth magnetic sensor 46 d, and a storage part 52.

The input part 51 previously inputs information such as a forming shape,a forming pressure, and a forming speed. The storage part 52 storestherein the information input from the input part 51 and a shapingprocess and outputs them to the controller 50. The first to fourthmagnetic sensors 46 a to 46 d measure displacements and speeds thereoffrom the scales of the respective first to fourth magnetic scales 47 ato 47 d disposed opposite thereto and output them to the controller 50.

The first to fourth drive parts 45 a to 45 d preferably feed back acurrent signal, a rotation speed signal, a torque signal, and the liketo the controller 50.

The following describes the operation of the three-dimensional shapingapparatus 1 according to the present embodiment.

FIGS. 6 to 9 are enlarged views each illustrating an operation of theshaped article placing part of the three-dimensional shaping apparatusaccording to the present embodiment.

First, in the three-dimensional shaping apparatus 1 according to thepresent embodiment, the drive part 45 illustrated in FIG. 4 is driven tomove downward the table 41 as illustrated in FIG. 6. The moving amountof the table 41 is previously input to the input part 51 illustrated inFIG. 5 and then stored in the storage part 52.

In the three-dimensional shaping apparatus 1 according to the presentembodiment, while the table 41 is moved by the moving amount stored inthe storage part 52, the current, rotation speed, and torque signals ofthe respective first to fourth drive parts 45 a to 45 d and measurementsignals from the respective first to fourth magnetic sensors 46 a to 46d are input to the controller 50.

The controller 50 independently controls the first to fourth drive parts45 a to 45 d on the basis of the above signals to thereby control thetable 41 to a predetermined posture. In the present embodiment, thetable 41 is made horizontal.

Subsequently, the metal powder M is discharged onto the table 41 fromthe discharge part 31 b of the powder storage part 31. Then, the metalpowder M on the table 41 is leveled by the leveling part 32 in such away that the surface thereof is horizontal. Subsequently, the energybeam irradiation part 2 illustrated in FIG. 1 emits the energy beam EBto sinter the metal powder M, thereby forming a part of a shaped articleM′, as illustrated in FIG. 7.

Then, the drive part 45 illustrated in FIG. 4 is driven again to movedownward the table 41, as illustrated in FIG. 8. The moving amount ofthe table 41 is previously input to the input part 51 illustrated inFIG. 5 and then stored in the storage part 52.

Then, in the same way as above, in the three-dimensional shapingapparatus 1 according to the present embodiment, while the table 41 ismoved by the moving amount stored in the storage part 52, the current,rotation speed, and torque signals of the respective first to fourthdrive parts 45 a to 45 d and measurement signals from the respectivefirst to fourth magnetic sensors 46 a to 46 d are input to thecontroller 50.

The controller 50 independently controls the first to fourth drive parts45 a to 45 d on the basis of the above signals to thereby control thetable 41 to a predetermined posture. In the present embodiment, thetable 41 is made horizontal.

Subsequently, the metal powder M is discharged onto the table 41 fromthe discharge part 31 b of the powder storage part 31. Then, the metalpowder M on the table 41 is leveled by the leveling part 32 in such away that the surface thereof is horizontal. Subsequently, the energybeam irradiation part 2 illustrated in FIG. 1 emits the energy beam EBto sinter the metal powder M, thereby forming a part of a shaped articleM′, as illustrated in FIG. 9.

FIG. 10 is a view illustrating a state where a shaped article is formedby the three-dimensional shaping apparatus according to the presentembodiment.

By operating the three-dimensional shaping apparatus according to thepresent embodiment as illustrated in FIGS. 6 to 9, the shaped article M′is formed as illustrated in FIG. 10.

The first to fourth drive parts 45 a to 45 d are provided independentlyof one another as described above, so that the posture of the table 41can be set in various patterns, enabling shaped articles M′ of varioustypes to be formed.

Further, it is possible to control the table 41 to a predeterminedposture by independently controlling the first to fourth drive parts 45a to 45 d, so that shaped article M′ of various types can be formed withhigh accuracy.

Furthermore, the controller 50 independently controls the first tofourth drive parts 45 a to 45 d to thereby make the table 41 horizontal,thus enabling the shaped article M′ to be formed with high accuracy.

FIG. 11 is a view illustrating a three-dimensional shaping apparatusaccording to another embodiment of the present invention. FIG. 12 is aschematic view illustrating an arrangement in the drive transmissionpart of the three-dimensional shaping apparatus according to the anotherembodiment.

In the another embodiment of the three-dimensional shaping apparatus 1illustrated in FIGS. 11 and 12, a fifth drive part 45 e, a fifthdeceleration part 44 e, and a fifth ball screw 43 e are provided belowthe center portion of the table 41. The five drive parts 45 arepreferably controlled independently of one another.

By thus supporting the table 41 at the five positions and driving thetable 41 using the five drive parts 45, the shaped article M′ can beformed with higher accuracy while securing horizontal accuracy of thetable 41. Further, a large-sized shaped article having heavy weight andlarge area can be placed.

FIG. 13 is a schematic view illustrating an arrangement in the drivetransmission part of a three-dimensional shaping apparatus according toa still another embodiment.

In the still another embodiment of the three-dimensional shapingapparatus 1 illustrated in FIG. 13, only a first ball screw 43 a isprovided. In this case, unillustrated only one drive part 45 ispreferably controlled.

By thus supporting the table 41 at the single position and driving thetable 41 using the unillustrated single drive part 45, the number of theball screws 43, deceleration parts 44, and drive parts 45 can bereduced, whereby the shaped article M′ can be formed at low cost.

Preferably, the first ball screw 43 a that supports the table 41 isdisposed at the centroid position of the table 41 so as to stabilize theposture of the table 41.

FIG. 14 is a schematic view illustrating an arrangement in the drivetransmission part of a three-dimensional shaping apparatus according toa still another embodiment.

In the still another embodiment of the three-dimensional shapingapparatus 1 illustrated in FIG. 14, at least two first and second ballscrews 43 a and 43 b are provided. In this case, unillustrated two driveparts 45 are preferably controlled independently.

By thus supporting the table 41 at the two positions and driving thetable 41 using the unillustrated two drive parts 45, the number of theball screws 43, deceleration parts 44, and drive parts 45 can bereduced, whereby the shaped article M′ can be formed at low cost.

Preferably, the first and second ball screws 43 a and 43 b that supportthe table 41 are disposed in such a way that a line connecting the firstand second ball screws 43 a and 43 b includes the centroid of the table41 so as to stabilize the posture of the table 41.

FIG. 15 is a schematic view illustrating an arrangement in the drivetransmission part of a three-dimensional shaping apparatus according toa still another embodiment.

In the still another embodiment of the three-dimensional shapingapparatus 1 illustrated in FIG. 15, three first to third ball screws 43a to 43 c are disposed in a triangle. In this case, unillustrated threedrive parts 45 are controlled preferably independently.

By thus supporting the table 41 at the three positions and driving thetable 41 using the unillustrated three drive parts 45, a plane isdefined to stabilize the posture of the table 41. In addition, thenumber of the ball screws 43, deceleration parts 44, and drive parts 45can be reduced, whereby the shaped article M′ can be formed at low cost.

Preferably, the first to third ball screws 43 a to 43 c that support thetable 41 are disposed in such a way that the triangle formed by thefirst to third ball screws 43 a to 43 c includes the centroid of thetable 41 so as to stabilize the posture of the table 41.

FIG. 16 is a schematic view illustrating a structure of the drivetransmission part of the three-dimensional shaping apparatus accordingto the present embodiment.

In the present embodiment illustrated in FIG. 16, a screw part 432 ofthe ball screw 43 is rotated by the drive force of the drive part 45 tovertically move a nut part 431, thereby vertically moving the table 41through the slider 42. The nut part 431 and the table 41 may directly beconnected to each other.

The nut part 431 is constituted of a nut 431 a and a case 431 bsurrounding the nut 431 a. The case 431 b is fixed to the slider 42. Thenut 431 a can be rotated with respect to the case 431 b. The screw part432 is rotatably fixed to the slider 42 at its upper portion, screwed tothe nut 431 a immediately below the slider 42, and connected, through acoupling, to the deceleration part 44 at its lower portion. The screwpart 432 penetrates a spline nut 433 fixed to the reference frame 12.

A drive force generated from the drive part 45 rotates the screw part432 through the deceleration part 44. The rotation of the screw part 432rotates the nut 431 a of the nut part 431. The nut part 431 can bevertically moved along the screw part 432, so that when the nut 431 a isrotated, the slider 42 is vertically moved to thereby vertically movethe table 41.

FIG. 17 is a schematic view illustrating a structure of the drivetransmission part of a three-dimensional shaping apparatus according toanother embodiment.

In the another embodiment illustrated in FIG. 17, the screw part 432 ofthe ball screw 43 is rotated by the drive force of the drive part 45 tovertically move the nut part 431, thereby vertically moving a movableframe 411, which vertically moves the table 41 through a rod 412 and theslider 42. The rod 412 and the table 41 may directly be connected toeach other.

The nut part 431 is constituted of the nut 431 a and the case 431 bsurrounding the nut 431 a. The case 431 b is integrally fixed to themovable frame 411. The screw part 432 is fixed to the support frame 11at its upper portion, penetrates the movable frame 411, screwed to thenut 431 a immediately below the movable frame 411, and connected,through a coupling, to the deceleration part 44 at its lower portion.

A drive force generated from the drive part 45 rotates the screw part432 through the deceleration part 44. The rotation of the screw part 432rotates the nut 431 a of the nut part 431. The nut part 431 can bevertically moved along the screw part 432, so that when the nut 431 a isrotated, the slider 42 is vertically moved through the movable frame 411and rod 412 to thereby vertically move the table 41.

FIG. 18 is a schematic view illustrating a structure of the drivetransmission part of a three-dimensional shaping apparatus according tostill another embodiment.

In the still another embodiment illustrated in FIG. 18, the nut 431 a ofthe nut part 431 is rotated by the drive force of the drive part 45 tovertically move the screw part 432 of the ball screw 43, therebyvertically moving the table 41 through the slider 42. The screw part 432and the table 41 may directly be connected to each other.

The nut part 431 is constituted of the nut 431 a and the case 431 bsurrounding the nut 431 a. The case 431 b is fixed to a nut support part41 b fixed to the reference frame 12. Thus, the nut part 431 cannot bevertically moved. The nut 431 a can be rotated with respect to the case431 b. The screw part 432 is rotatably fixed to the table 41 at itsupper portion and screwed to the nut 431 a at its lower portion. Thescrew part 432 penetrates the spline nut 433 fixed to the referenceframe 12.

A first pulley 401 is fixed to an output shaft 44 a of the decelerationpart 44. A second pulley 402 is fixed to the nut 431 a. The first pulley401 and the second pulley 402 are connected to each other by aconnection belt 403. The second pulley 402 is rotated together with thenut 431 a of the nut part 431 to allow the screw part 432 to penetratetherethrough.

A drive force generated from the drive part 45 is output to the firstpulley 401 through the output shaft 44 a of the deceleration part 44.When the first pulley 401 is rotated, the second pulley 402 is rotatedthrough the connection belt 403. The rotation of the second pulley 402rotates the nut 431 a of the nut part 431. The nut part 431 cannot bevertically moved, so that when the nut 431 a is rotated, the screw part432 is vertically moved. As a result, the table 41 is vertically moved.

FIG. 19 is a schematic view illustrating a structure of the drivetransmission part of a three-dimensional shaping apparatus according tostill another embodiment.

In the another embodiment illustrated in FIG. 19, the nut 431 a of thenut part 431 is rotated by the drive force of the drive part 45 tovertically move the nut part 431 of the ball screw 43 with respect tothe screw part 432, thereby vertically moving the movable frame 411,which vertically moves the table 41 through the rod 412 and slider 42.The rod 412 and the table 41 may directly be connected to each other.

The nut part 431 is constituted of the nut 431 a and the case 431 bsurrounding the nut 431 a. The case 431 b is fixed to the nut supportpart 41 b fixed to the movable frame 411, whereby the nut part 431 isintegrally fixed to the movable frame 411. Further, the drive part 45and the deceleration part 44 are also integrally fixed to the movableframe 411 and are thus vertically moved together with the movable frame411.

The screw part 432 is fixed to the support frame 11 at its upper portionand screwed to the nut 431 a at its lower portion. The screw part 432penetrates the spline nut 433 fixed to the movable frame 411.

The first pulley 401 is fixed to the output shaft 44 a of thedeceleration part 44. The second pulley 402 is fixed to the nut 431 a.The first pulley 401 and the second pulley 402 are connected to eachother by the connection belt 403. The second pulley 402 is rotatedtogether with the nut 431 a of the nut part 431 to allow the screw part432 to penetrate therethrough.

A drive force generated from the drive part 45 is output to the firstpulley 401 through the output shaft 44 a of the deceleration part 44.When the first pulley 401 is rotated, the second pulley 402 is rotatedthrough the connection belt 403. The rotation of the second pulley 402rotates the nut 431 a of the nut part 431. The screw part 432 cannot bevertically moved, so that when the nut 431 a is rotated, the nut 431 ais vertically moved. Accordingly, the movable frame 411 is verticallymoved together with the nut part 431, whereby the slider 42 and thetable 41 connected to the movable frame 411 are vertically moved.

FIG. 20 is a schematic view illustrating a structure of the drivetransmission part of a three-dimensional shaping apparatus according tostill another embodiment.

In the still another embodiment illustrated in FIG. 20, a hollow directdrive motor is used as the drive part 45 to rotate the nut 431 a,thereby vertically moving the screw part 432 of the ball screw 43, whichvertically moves the table 41 through the slider 42. The screw part 432and the table 41 may directly be connected to each other.

The drive part 45 uses the hollow direct drive motor to drive the nut431 a to allow the screw part 432 to penetrate therethrough at thecenter thereof.

The nut part 431 includes the nut 431 a inside thereof and is fixed tothe reference frame 12 so as not to be vertically moved. The nut 431 acan be rotated with respect to the case 431 b. The screw part 432 isrotatably fixed to the table 41 at its upper portion and screwed to thenut 431 a at its lower portion.

When the drive part 45 generates a drive force, the nut 431 a of the nutpart 431 is rotated. The nut part 431 cannot be vertically moved, sothat when the nut 431 a is rotated, the screw part 432 is verticallymoved. As a result, the table 41 is vertically moved.

FIG. 21 is a schematic view illustrating a structure of the drivetransmission part of a three-dimensional shaping apparatus according tostill another embodiment.

In the still another embodiment illustrated in FIG. 21, a hollow directdrive motor is used as the drive part 45 to rotate the nut 431 a. Thisvertically moves the screw part 432 of the ball screw 43 to verticallymove the movable frame 411, thereby vertically moving the table 411through the rod 412 and slider 42. The rod 412 and the table 41 maydirectly be connected to each other.

The drive part 45 uses the hollow direct drive motor to drive the nut431 a to allow the screw part 432 to penetrate therethrough at thecenter thereof.

The nut part 431 is constituted of the nut 431 a and the case 431 bsurrounding the nut 431 a. The case 431 b is fixed to the movable frame411. The nut 431 a can be rotated with respect to the case 431 b. Thescrew part 432 is fixed to the frame 11 at its upper portion and screwedto the nut 431 a at its lower portion.

When the drive part 45 generates a drive force, the nut 431 a of the nutpart 431 is rotated. The rotation of the nut 431 a vertically moves thenut 431 a along the screw part 432. Accordingly, the movable frame 411is vertically moved together with the nut part 431, thereby verticallymoving the slider 42 and table 41 connected to the movable frame 411through the rod 412.

The same control system as that described in FIG. 5 may be used in allof the above embodiments related to the arrangements in the drivetransmission part and the structure of the drive transmission part ofthe three-dimensional shaping apparatus 1.

The three-dimensional shaping apparatus 1 includes the support frame 11,the material supply part 3 supported by the support frame 11, and theshaped article placing part 4 which is supported by the support frame 11and on which a material supplied from the material supply part 3 isplaced. The shaped article placing part 4 includes the table 41 on theupper surface of which a shaped article is placed, the drive part 45that drives the table 41, the measurement part 46 that measures theposition of the table 41, and the controller 50 that controls the drivepart 45 on the basis of a measurement value from the measurement part46. Thus, a three-dimensional shaping apparatus excellent in accuracyand productivity can be provided.

The three-dimensional shaping apparatus 1 according to the presentembodiment includes the input part 51 that previously inputs thereto themoving amount of the table 41 and the storage part 52 that stores themoving amount input thereto from the input part 51. The controller 50moves the table 41 by the moving amount stored in the storage part 52.Thus, appropriate control can be achieved.

In the three-dimensional shaping apparatus 1 according to the presentembodiment, the state signals of the drive part 45 are fed back to thecontroller 50, enabling highly accurate control.

The drive part 45 includes the first and second drive parts 45 a and 45b which can be independently driven. The measurement part 46 includesthe first and second magnetic sensors 46 a and 46 b that measure theposition of the table 41. The controller 50 independently controls thefirst and second drive parts 45 a and 45 b on the basis of measurementvalues from the first and second magnetic sensors 46 a and 46 b. Thus, athree-dimensional shaping apparatus excellent in accuracy andproductivity can be provided.

The three-dimensional shaping apparatus 1 according to the presentembodiment further includes the transmission part 43 having the firstand second ball screws 43 a and 43 b that transmit drive forces suppliedfrom the respective first and second drive parts 45 a and 45 b to theslider 42, thus enabling smooth movement of the table 41.

In the three-dimensional shaping apparatus 1 according to the presentembodiment, the first and second magnetic sensors 46 a and 46 b aredisposed so as to correspond to the positions of the first and secondball screws 43 a and 43 b that support the table 41, enabling highlyaccurate control.

In the three-dimensional shaping apparatus 1 according to the presentembodiment, the drive part 45 includes the first to fourth drive parts45 a to 45 d arranged in a rectangular shape. The transmission part 43includes the first to fourth ball screws 43 a to 43 d that transmitdrive forces supplied from the respective first to fourth drive parts 45a to 45 d to the table 41. The controller 50 can independently controlthe first to fourth drive parts 45 a to 45 d. Thus, more highly accuratecontrol can be achieved.

The three-dimensional shaping apparatus 1 according to the presentembodiment includes the rod 48 moved together with the table 41 and thelimit switch 49 put in contact with the rod 48 when the rod 48 reaches apredetermined position, thus preventing the table 41 from beingexcessively moved.

The present invention is not limited to the above-described embodiments.That is, while the description of the embodiments includes specific anddetailed contents for exemplification, variations or modifications maybe applied to these detailed contents.

REFERENCE SIGNS LIST

-   1: Three-dimensional shaping apparatus-   11: Support frame-   12: Reference frame (support frame)-   2: Energy beam irradiation part (material supply part)-   21: Beam generation part-   22: Beam scanning part-   3: Powder supply part (material supply part)-   31: Powder storage part-   32: Leveling part-   33: Outer frame part-   4: Shaped article placing part-   41: Table-   42: Slider-   43: Ball screw (transmission part)-   44: Deceleration part (transmission part)-   45: Drive part-   46: Magnetic sensor (measurement part)-   47: Magnetic scale (measurement part)-   48: Rod-   49: Limit switch-   50: Controller-   51: Input part-   52: Storage part

The invention claimed is:
 1. A three-dimensional shaping apparatuscharacterized by comprising: a support frame; a powder material supplypart supported by the support frame; and a shaped article placing partwhich is supported by the support frame and on which a powder materialsupplied from the powder material supply part is placed, wherein theshaped article placing part includes: one and only one table on an uppersurface of which a shaped article is placed; a plurality of drive partsthat drives the table; a measurement part that measures the position ofthe table; a controller that controls the drive part on the basis of ameasurement value from the measurement part; a rod moved together withthe table, the rod being provided in a direction perpendicular to asurface of the table; and a limit switch put in contact with the rodwhen the rod reaches a predetermined position, wherein the table has aunitary structure driven by the plurality of drive parts, wherein eachof the plurality of drive parts is independently driven, wherein theplurality of drive parts includes first and second drive parts which canbe independently driven, wherein the measurement part includes first andsecond measurement parts that individually measure the position of thetable, wherein the controller independently controls the first andsecond drive parts on the basis of measurement values from the first andsecond measurement parts, wherein the unitary structure has a planarupper surface extending over the plurality of drive parts, and whereinthe limit switch is not in contact with the rod when the rod does notreach to the predetermined position.
 2. The three-dimensional shapingapparatus according to claim 1, characterized by further comprising: amotor encoder that previously inputs thereto the moving amount of thetable; and a memory that stores the moving amount input thereto from themotor encoder, wherein the controller moves the table by the movingamount stored in the memory.
 3. The three-dimensional shaping apparatusaccording to claim 1, characterized in that state signals of theplurality of drive parts are fed back to the controller.
 4. Thethree-dimensional shaping apparatus according to claim 1, characterizedin that the shaped article placing part further includes a transmissionpart having first and second transmission parts that individuallytransmit drive forces supplied from the respective first and seconddrive parts to the table.
 5. The three-dimensional shaping apparatusaccording to claim 4, characterized in that the first and secondmeasurement parts are disposed so as to correspond to the positions ofthe first and second transmission parts that support the table.
 6. Thethree-dimensional shaping apparatus according to claim 5, characterizedin that the plurality of drive parts includes the first drive part, thesecond drive part, a third drive part and a fourth drive part arrangedin a rectangular shape, the transmission part includes first to fourthtransmission parts that transmit drive forces supplied from therespective first to fourth drive parts to the table, and the controllercan independently control the first to fourth drive parts.